Emily Dickinson Lexicon

BROTH'ER, n. [plur. Brǒthers or Brethren. Goth. brothar; Sax. brother or brether; Sw. and Dan. broder; D. broeder, from broeden, to brood, to breed; G. bruder; Sans. brader or bhratre; Russ. brat; Dalmatian brath; L. frater; Gr. φρατηρ, φρατωρ; Pers. بُرَادَرْ boradar; Corn. bredar; Ir. brathair; W. brawd; Sam. abrat; Fr. frère, from L. frater; Sp. frayle, a friar; It. fratello, brother, and frate, friar; Arm. breuzr. By the Dutch, it appears that this word signifies one of the brood or breed. The common plural is brothers, in the solemn style brethren is used.]

1. A human male born of the same father and mother. A male by one of the parents only is called a half-brother, or brother of the half blood. – Blackstone.
2. Any one closely united; an associate; as, a band of brothers.
3. One that resembles another in manners. He that is slothful in his work is brother to him that is a great waster. – Proverbs xviii. In Scripture the term brother is applied to a kinsman by blood more remote than a son of the same parents; as in the case of Abraham and Lot, Jacob and Laban. Persons of the same profession call each other brother, as judges, clergy-men, professors of religion, members of societies united in a common cause, monks and the like. Kings give to each other the title of brother. Clergymen address their congregations by the title of brethren. In a more general sense, brother or brethren is used for man in general; all men being children of the same primitive ancestors, and forming one race of beings. Brother-german is a brother by the father's and mother's side, in contradistinction to a uterine brother, or by the mother only. – Encyc.